- The delay between the decision to resuscitate the patients with fluids and randomisation should be as short as possible (15 minutes or less). Thus, the use of sealed envelopes seems to be the best method for allocation concealment in this case. There will be at each centre, 3 sets of sealed envelopes, one for each strata (i.e., trauma or hemorrhage, sepsis, and other diagnoses). To randomise a patient, the investigator must use the first available sealed envelope (according to allocation number) in the corresponding (i.e., trauma or hemorrhage, sepsis, other diagnoses).